How Worried Should You Be? Petrol in a Diesel Car in Toppings
Far less than you probably are, if it hasn't been started. Until your ignition primes the pump, your starter cranks, or the car is driven, petrol in a diesel tank just sits there and does nothing. Which makes the truthful reply to that first Toppings question — "have I ruined it?" — usually no. Keep it like that: leave your motor off and call Petrol in Diesel. Further down, you will find what petrol really does inside a diesel, how far it may have gone, and how to stop it happening to you again.
Inside your engine: what petrol in a diesel really does
Passing through an engine, diesel is doing two things at once. It protects to begin with, and after that does it burn. The high-pressure pump and the injectors are made to extremely fine clearances, and the diesel passing through them is what stops those surfaces from wearing down against one another.
Of those two jobs, petrol manages the first poorly and the second never. It's thinner than diesel and strips away the lubrication the fuel system hinges on, and so a pump running on a petrol mixture is a pump wearing itself. And petrol is designed to resist igniting under compression, which is the opposite of what a diesel needs from its fuel. That's where the rattling comes from.
Together, those leave the shape of the trouble plain. Not contact but circulation is what causes the damage. Any tank with petrol in it is a fuel problem. The beginning of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with the fuel to your injectors downstream.
Petrol in a diesel in Toppings: how serious is it? Four situations
Fuelled, and not started: nothing beats it. Only the tank has petrol in it, and so the task is draining that tank and purging your system where the vehicle sits. This scenario can only really happen at a forecourt: anywhere else, your car got there by being driven.
Ignition on, or started for a moment. The system has been bled, so petrol has left the tank and reached your filter and your lines. Still usually straightforward: drain, flush, and your filter sorted.
Driven a couple of miles. Now your pump has spent these miles working on weakened fuel. How hard the vehicle was driven counts as much as how far, and the work takes in that tank, the fuel lines, the fuel filter and fresh fuel through the whole system. On the school run to Eagley Junior School, the mileage is small. Getting as far as Salford, under 15 miles away, makes a very different task — as does any mileage on the M66, under 5 miles from Toppings, with the motor running hard the whole time.
It protested, and only then stopped: smoke, rattling, a throttle gone soft, an idle gone uneven. What you are hearing is the engine reporting fuel that no longer runs like diesel. Whether it's the verge on Bromley Cross Road, a lay-by or a side street, stop there and leave it. The drain and flush still go first, and they take care of it: when a car is stopped early, permanent damage is very unusual.
Toppings motorists and the petrol in a diesel myths they hear
"Top it up the rest of the way with diesel and it'll be fine" — a myth. It won't. Nothing is removed by topping up — you are left with a fuller tank, still the same mix. A diesel fuel system doesn't accept petrol by percentage in the way that advice supposes.
"Newer diesels can handle a little petrol" — a myth, and nearer the opposite. Smaller parts and higher pressure are how a current diesel runs its fuel, and that makes the protection matter more, not less.
Myth: "If it starts and drives, there's no damage done." This is the one that catches drivers. Feed diesel to a petrol motor and it generally will not run, and so the driver stops — and the harm stops with them. Nothing looks to have happened when a diesel fed petrol fires up, ticks over and drives away, as it usually does; meanwhile the pump wears. Fine and running aren't the same at all.
An old fix for a distinct fault is behind this one. Myth: "Add some two-stroke oil and drive the vehicle home." What petrol has diluted stays weakened, and the petrol stays inside the tank anyway.
"Drain it yourself and you're sorted" — a myth, since after it has been running some petrol sits in the filter and lines, waiting to go right back through the pump at your next start. On top of that, petrol cleared into a can by the road is genuinely risky.
How does petrol in a diesel occur?
A careless moment is seldom the cause, and nobody means to do it. One way only, since of the nozzles: the narrower petrol one slips inside a diesel filler with almost no resistance, whereas the diesel one generally won't fit a petrol vehicle. That is how the forecourt makes it straightforward.
Routine and the car getting out of step is when it occurs. A new vehicle, a hire car or a courtesy car. Households running one of each, petrol and diesel. A forecourt you know, but with its pumps laid out differently. A rushed fill on the way to Bromley Cross with a train to catch. The first fill-up in a diesel Renault Clio after years of driving petrol is exactly the moment it takes place. Throw in rain, a phone call or a back seat full of kids, and your hand repeats what it has always done.
Preventing petrol in a diesel next time you fill up in Toppings
- Green for unleaded and black for diesel is normal in the UK — but not on each forecourt. Trust the label on the pump, not the colour.
- The first fill in a strange vehicle is the time to check your filler flap — on it, or on the cap, plenty of motors state which fuel to use.
- Good intentions count for less than a sticker or a fob in a bright colour on the diesel's key if a house has one of each. So label it.
- Say it before you lift it. On the first fill in a new or hired car, say "diesel" out loud before you take the nozzle off the pump. It seems daft and it does the trick.
- While you are thinking about something else, this is an easy mistake to make — so put your phone away.
- A misfuel inhibitor helps, up to a point. Some diesels come with a filler designed to refuse a petrol nozzle, and add-on devices exist for vehicles without one. They are a safety net, not a reason to stop reading the pump.
- Stop as soon as you notice. Less petrol inside that tank makes a thinner blend. It doesn't change what to do next, which is still not to crank it.
Already put petrol in a diesel around Toppings?
The order of things is short, then. Leave it unstarted, with your ignition switched off as well. The staff at the forecourt — whether at BP itself or wherever you filled up — will usually help push it away from the petrol pump if you ask. Then phone 0333 366 0103 and tell us what went in, about how much, and if it's run.
Say so if it was AdBlue rather than petrol: it is a separate fault, with its own page for Toppings, because AdBlue brings corrosion and deposits instead of lost lubrication.
Why one petrol in a diesel task around Toppings costs more than another
Four separate tasks lie behind the four scenarios above — which is why there's no fair single price. The scenario itself does most of the work of moving your cost. Beyond that it is the ratio — how much petrol got in against how much your tank holds — and then where the vehicle is and whether a van can get to it safely.
What was put in, how much, and whether it's run — three queries we ask before pricing, not after, for exactly that reason. A range turns into a straight figure when the replies are in.
About Toppings
Toppings is a suburban area in Greater Manchester, situated near the River Irwell and characterised by semi-detached housing. Toppings sits at an elevation of 152 metres, approximately 10.5 miles from Salford and near the communities of Bromley Cross, Eagley, and Cox Green. Toppings is home to around 4739 residents, who enjoy a relatively quiet riverside setting within the larger North West region.
Toppings and Greater Manchester: where our fuel drain cover reaches
The teams answering petrol in diesel call-outs in Toppings, in the BL postcode area, equally work the locations around it, Bromley Cross, Eagley and Cox Green included. The car doesn't need to move to us: our engineers drain on a forecourt, in a supermarket car park, in a lay-by or on your own drive.
Still at the petrol pump around Toppings?
The best spot there is, then — that's where you are. Leave it switched off, and ring.